Apple released its newest mobile operating system, iOS 9, to the public on September 16. The new OS provides some significant improvements to mobile application development, especially for iPad. The major updates have presented tech giants and entrepreneurs with opportunities to deliver better apps.

Multitasking

One of the most noticeable updates in iOS 9 is multitasking on the large screen of the iPad. Multitasking allows users to show two apps on the screen at once – something quite familiar to desktop users, but new on Apple mobile devices. It has three modes: Slide Over, Split view and Picture-in-Picture (PIP).

Slide Over allows the user to get a glimpse of one app in a side panel while another app remains full screen behind it. Updates to an email inbox or Twitter feed can be read quickly, with minimal interruption.

The second major change is Split View. With this you can work on two apps at once independently of each other while both are fully functional. Each panel is resizable, so the apps can take up similar amounts of space or be portioned out according to need.

Finally, there’s Picture-in-Picture (PIP) video. This enables a user to play video or participate in a FaceTime conversation while using other apps. Pressing the Home button rescales the video and leaves the rest of the display available for another app. The iOS 9 player will remain on top.

Because of the demands on graphics hardware, not all iPads support all multitasking features, even if they can be updated to iOS 9. Slide Over and PIP work on iPad Pro, iPad Air or later, and iPad mini 2 or later. Split View requires iPad Pro, iPad Air 2, or iPad mini 4.

Apps do need to be optimized to work as well as possible with the three multitasking modes. Developers can take advantage of Auto-Layout and Size-Classes elements in their code so that text and graphics reflow sensibly as panels are resized. If you need to ask yourself, "Will my app work well with this?" it couldn’t hurt to test it out on recent Apple iPads.

Improved search

The powerful new search API in iOS 9 provides deeper search powers into any app. The deep linking or universal linking feature enables users to easily search and access content from or within third-party apps. For example, if you have an app that books hotel rooms, when the user searches for "Niagara Falls" your app shows up with lists of hotels near Niagara Falls; when the user clicks on that search result, the exact screen in your app for booking that hotel opens.

App thinning

No matter how awesome your app, it’s always best to be as lean on size as you can. Large app sizes are a huge turn off for users because it not only takes longer to download but also consumes valuable local storage space.

App thinning is all about slicing an app into its component parts. This ensures that your app will use the minimum storage space on users’ devices. It supports downloading only the bits of the app needed by that particular device, based on things like screen resolution and hardware components. This enables users to download your app specially optimized for their device.

Apps can be bloated by having artwork of all different resolutions for different devices packaged together. Functions that don’t work on some hardware – say, Apple Pay or fingerprint recognition on an iPhone 5s – simply waste space. Allowing build support for the following app thinning solutions gives your app users a smaller and convenient way to download your app.

Slicing: If your app separates multi resolution artwork using asset bundles, you are mostly set. Developers can also add additional device filters on different assets to make use of this feature. The App Store only sends those assets matching the users’ device when users download an app, thereby significantly cutting down on download times.

On Demand Resources: Using a new API available on iOS 9, developers can designate certain assets to download on an as-needed basis. Earlier, developers needed a costly custom server to do something similar, but native support within the App Store reduces that burden considerably.

BitCode: BitCode allows developers to submit an intermediate representation of your code rather than the final binary to the App Store. Apple will compile the bitcode to the actual binary pushed to a device while applying optimizations and bug fixes at their end. This means Apple takes away all the trouble of having the developers optimizing code specific to different hardware.

If you’ve released an app and want to make it fully compatible with iOS 9 – or just want to build a brand new app – email us or call 603.881.9200.